Soft erythrocyte-based bacterial microswimmers for cargo delivery.

Area of Science:

• Biomedical Engineering
• Microfluidics
• Nanotechnology

Background:

• Bacteria-propelled microswimmers offer active cargo transport but synthetic carriers limit clinical use.
• Red blood cells (RBCs) present a biocompatible and biodegradable alternative for cargo encapsulation.

Purpose of the Study:

• To develop bacteria-driven microswimmers using RBCs as autologous cargo carriers for guided drug delivery.
• To enhance biocompatibility, biodegradability, and performance of biohybrid microswimmers for medical applications.

Main Methods:

• Fabrication of biohybrid microswimmers by attaching RBCs (loaded with doxorubicin and SPIONs) to motile Escherichia coli.
• Utilizing biotin-avidin-biotin complex for RBC-bacteria attachment.
• Incorporating superparamagnetic iron oxide nanoparticles (SPIONs) for magnetic guidance and a light-activated switch for bacteria control.

Main Results:

• Bacteria provided autonomous propulsion, while SPIONs enabled magnetic guidance.
• RBC-based microswimmers maintained deformability and stability in microchannels.
• A light-activated system was engineered to control bacteria population post-operation.

Conclusions:

• RBCs offer superior stability, deformability, biocompatibility, and biodegradability compared to synthetic carriers.
• This biohybrid microswimmer design transforms RBCs into active, guidable cargo carriers for targeted delivery.
• The developed system shows significant potential for future medical applications in drug and cargo delivery.